Researchers have synthesized a novel biocompatible and biodegradable hydrogel that can slowly release the antiamoebic ornidazole and the antibiotic ciprofloxacin1. The hydrogel releases the drugs in response to external stimuli such as changes in temperature and pH. It raises the possibility of delivering two drugs simultaneously and hence could be effective for administering treatments that involve using two drugs.

The researchers synthesized the porous hydrogel by chemically linking dextrin with polyacrylic acid using methylene bisacrylamide, a linker compound. They then loaded the hydrogel with ornidazole and ciprofloxacin.

They found that the diffusion rate of water molecules through the network of polymers in the hydrogel increased with increasing temperature. These rates were higher in alkaline media than in acidic causing the hydrogel to absorb water and swell faster than in acidic media. This resulted in better sustained release of ornidazole and ciprofloxacin in alkaline media.

The hydrogel was biocompatible (it did not show any toxic effects on human mesenchymal stem cells) and biodegradable (it progressively lost mass when left in hen egg lysozyme analogous to human lysozyme).

“The technique could be applied to synthesize other types of functional porous hydrogels,” says lead researcher Sagar Pal.

The authors of this work are from: Polymer Chemistry Laboratory, Department of Applied Chemistry, Indian School of Mines, Dhanbad, Biomaterials and Tissue Engineering Laboratory, School of Medical Science and Technology, Indian Institute of Technology, Kharagpur and Discipline of Inorganic Materials and Catalysis, Central Salt and Marine Chemicals Research Institute (CSIR), Bhavnagar, Gujarat, India